VisuaIizing universes of knowledge: design and visual analysis of the UDC

: In the 1950s, the "universe of knowledge" metaphor returned in discussions within an "universe of concepts"system. around the "first theory of faceted classification'i the Colon Classification (CC) of S.R. Ranganathan, to stress the differences Classification Here we claÍm that the Universal Decimal (UDC) has been either ignored or incorrectly represented in studies that focused on the pivotal role of Ranganathan in a transition from "top-down universe of concepts systems" to "bottom-up universe of concepts systems." Early 20th century designs from Paul Otlet reveal a two directional interaction between'êlements"and "ensembles"that of 1 908 includes sketches Group design and visual can be compared to the relations between the universe of knowledge and universe of concepts systems. Moreover, an unpublished manuscript with the title "Théorie schématique de la Classification" that demonstrate an exploration by Paul Otlet of the multidimensional characteristics of the UDC. The interactions between these one- and multidimensional representations of the UDC support Donker Duyvis'critical comments to Ranganathan who had dismissed it as a rigid hierarchical system in comparison to his own Colon Classification. A visualization of the experiments of the Knowledge Space Lab in which main categories of Wikipedia were mapped on the UDC provides empirical evidence of its faceted structure's flexibility.